1. Field of the Invention
This invention relates to circuit assembly apparatus and, more specifically, to apparatus used to facilitate preparation of breadboard circuits.
2. Description of Prior Art
In the design of almost all circuits, it becomes necessary at some point to fabricate the circuit to ascertain its workability. To facilitate fabrication of experimental circuits, numerous techniques have been devised for simplifying the bread-boarding procedure. One example of apparatus used to facilitate breadboard circuit fabrication is disclosed in R. R. Scoville U.S. Pat. No. 2,947,965, issued Aug. 2, 1960. Scoville discloses a push-in terminal lug having a slot at one end for engaging cross-connection wiring and a pair of slots at an opposite end, one of which has a sawtooth-shaped pattern along its inner edges for engaging lumped element circuit components. While the Scoville apparatus may be suitable for lumped circuit components, such as resistors, capacitors and the like, with the advent of miniaturized integrated circuit packages with their fragile leads, the Scoville-type apparatus is wholly unsatisfactory in fabricating large-scale circuits of the type encountered in computer and communication circuit applications.
Another device developed to assist in breadboard circuit applications is disclosed in W. R. Evans U.S. Pat. No. 3,824,527, issued July 16, 1974. Evans discloses a wire-in-slot electrical connector which comprises a generally V-shaped member having wire-receiving slots extending into corresponding side edges. Plate sections of the "V" are kinked so that, upon insertion of a wire, the plate sections are resiliently stressed by the wire causing them to move toward each other. Similar to Scoville, Evans fails to address the problem of engagement of fragile leads emanating from a dual in-line integrated circuit package.
One example of a connector which has partially taken into account the engagement of fragile integrated circuit leads is disclosed in S. V. Horecky U.S. Pat. No. 3,621,334, issued Nov. 16, 1971. Horecky discloses a connector terminal which has a cylindrical-shaped hollow body with a single leaf spring emanating from one side. Upon insertion of a wire into the hollow cylinder, this leaf spring engages a side portion of the wire and holds it in place in the connector.
A more recent example of the attention directed to solution of the circuit breadboarding problem is evidenced by a copending application Ser. No. 630,183, filed Nov. 10, 1975, in the name of C. A. Von Roesgen, and assigned to the same assignee as the subject application. Von Roesgen relates to a quick connect breadboard system which utilizes an electrical connector having a generally circular terminal at one end for engaging a terminal pin on an integrated circuit package and a single insulation piercing-terminal at an opposite end.
While all of the aforementioned patents and applications have to some extent addressed the problem of facilitating quick connection of breadboard circuits, none of these patents or applications has taken into account the need for frequent changes which may arise and the further need to provide conductor support and electrical isolation at the various termination points. In particular, with respect to wiring changes, none of the referenced inventions, or wirewrapping systems for that matter, provide for ease in effecting such wiring changes.
Accordingly, it is one object of the present invention to facilitate rapid cross-connection of circuit nodes requiring interconnection in breadboard circuits.
Another object is to simplify the procedures needed to effect circuit wiring modifications.
Still another object of the present invention is to permit additional connections to the same connector without degrading the reliability of other connections already made thereon.
A further object is to provide conductor support and electrical isolation at all circuit termination points.
Still a further object of the present invention is to improve the reliability of electrical and mechanical connections with terminal pins on integrated circuit packages in breadboard wiring systems.
Yet another object is to shield termination points in breadboard circuits from environmental contaminants.